This is first one I have seen that integrated with BlackBerry's phone, contact, call log and sound profile system.
BlackVoib - A SIP VoIP Softphone for BlackBerry Devices
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BlackVoib version 1.5.0 released
The major feature addition in this version is Sound Profile Management integration into BlackVoib. If you are running OS late version 5 and OS 6 , you will be able to set the ring tones by editing the BlackVoib's Sound Profile. You can set it to loud, silence, or vibrate only, just like you normally do with your BlackBerry device. In addition, every call you made, received, missed will be logged in the BlackBerry Call Log.
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